Characteristics of a dusty nonthermal plasma from a particle-in-cell Monte Carlo simulation.

Abstract

Nonthermal dusty plasmas can be found in plasma-processing applications as well as in space phsyics. A model based on a particle-in-cell Monte Carlo simulation has been developed to study the physical properties of such plasmas and the plasma-dust particle interactions. Assuming a uniform dusty plasma with a given size and concentration of dust particles, the model provides self-consistently the average electric field necessary to sustain the plasma for a given current density flowing through it, the charge and floating potential of the dust particles, the potential distribution, and the velocity distribution functions of electrons and positive ions. The model has been applied to situations where the distance between dust particles is much smaller than the electron Debye length (particulates interact electrostatically with each other) as well as situations where the distance between dust particles is larger than the Debye length (particulates are isolated electrostatically from each other). Questions concerning the momentum and energy transfer from electrons and ions to dust particles are also discussed. Simple scaling laws are also derived and compared with the numerical results.